All the data was summarized at hexagon level (15 km diameter).
Variables Obtained from this data set:
Variables obtained from this data set:
Variables obtained from this data set:
Variables obtained from this data set:
Variables obtained from this data set:
Our model consist of two main components:
The local transmission is simulated using Ordinary Differential Equations where each hexagon has its own population parameters based on the population distribution, and its own transmission parameters based on the local activity observed in the network and the susceptibility of the local population.
The model is a simple SIR described as:
\[\frac{dS}{dt}=-\frac{\beta IS}{N} \\ \frac{dI}{dt} = \frac{\beta IS}{N} - \gamma I \\ \frac{dR}{dt} = \gamma I\]
Where the transmission parameter is weighted based on the number of observed movements within the hexagon to simulate the within hexagon transmission. The transmission parameter is bounded between \(0.01 > \beta > 3.5\). So when there is an absence of local trade for a given hexagon, the transmission parameter will be 0.01, and when there is a high local trade, the transmission parameter will be close to the upper bound.
The relationship between the probability of local trade happening has a relationship with the transmission parameter based on the function \(F(x) = \frac{1}{cos(x)}\)
The global transmission is modeled based on the observed trade patterns between hexagons. The daily probability and the expected number of animals moved was calculated based on the observed data and assigned to each hexagon along with a list of potential neighbors (destinations).
Based on the proportion of infected animals per hexagon, we calculated a probability of exporting infected animals. This probability follows a relationship based on the function \(F(x) = \frac{1}{cos(x)}\)